User talk:Cajb

Welcome!

Hello, Cajb, and welcome to Wikipedia! Thank you for your contributions. I hope you like the place and decide to stay. Here are some pages that you might find helpful:

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Some Wikipedia conventions

Hello. Your article q-Vandermonde identity prompts some tips concerning Wikipedia's conventions, outlined in Wikipedia:Manual of Style and, as they apply to mathematics article, to some extent in Wikipedia:WikiProject Mathematics:

Words should not be capitalized merely because they're in the title of a Wikipedia article, i.e. the title should be q-Vandermonde identity, with a lower-case initial i (I've moved it to that title) (the initial V is still capital since it's a person's name). The first letter of the article always appears as a capital but, unlike the later letters, is not case-sensitive in links.

The title word or title phrase should be in bold, like this, at its first appearance, usually very early in the article, and in fact usually in the first sentence (I've also taken care of this).

In non-TeX mathematical notation, variables (but NOT digits and NOT parentheses or other punctuation) should be italicized, thus: x + 2 = x². That way they match TeX style. Also, in non-TeX notation, a space should preceed and follow things like "+" and "=". Often you may want to make this a non-breakable space character, so that when you write x + 2, you won't see "x +" at the end of one line and "2" at the beginning of the next (where the line ends depends on the size and shape of the user's window). To see how to create the non-breakable space character, just click on "edit" on this talk page and see what I did when I typed x + 2. (In TeX, there is of course no need to think about any of this; the software does it automatically.) (Usually on Wikipedia, TeX looks very good when "displayed" but sometimes gets misaligned or otherwise looks bad when "inline".

You may want to consider which other articles should link to any new article you create. I've added q-Vandermonde identity to the list of combinatorics topics and to the "see also" section of q-analog. You can also add it to the list of mathematics articles. I think that happens automatically if you put one of the math-topic category tags on it, although it may take 24 hours or so.

Michael Hardy 21:07, 17 November 2006 (UTC)[reply]

I think I fixed it up a bit - Let me know if there is anything else that can be done. (Aside from completely finishing the article I've added the category links.)

- Cajb

I've moved Householder Operator (with a capital initial "O") to Householder operator (with lower-case). The article could also use some links---both from and to the article---and some initial context-setting (telling the lay reader it's math and not pharmacology, etc.) I'd have taken care of this but for another question about which I am uncertain: should this new article get merged into the older one called Householder transformation? Michael Hardy 00:32, 22 November 2006 (UTC)[reply]

Answering the second part first, I believe there is a correlation to the Householder transformation mentioned and this operator - but the two results seem to be a slight bit different. At first glance I thought the Householder transformation was the more general version, but then reading the final lines suggests that it uses the notion of dot products - the more specific version of inner products over real vector spaces. Okay I think I found something here:

"Note: If V is a real inner product space, then the language of Section 6.11, H_u is a reflection."

Friedberg, Stephen H., Arnold J. Insel, and Lawrence E. Spence. Linear Algebra. 4th ed. New Jersey: Pearson Education Inc., 2003. 397.

So it would appear that the Householder operator is the generalization of the Householder transformation since the Householder operator is valid over Complex Vector Spaces as well.

Secondly, my appologies for not quite finishing the article - been busy recently and was hoping to have more time than anticipated - links should be related to the Householder transformation (is there a site telling me how to change the name from Householder Operator to the small case o? I noticed the mistake but wasn't sure how to fix it and couldn't find the information) Let me know what you think of these changes.

- Cajb